(1) Field of the Invention
This invention relates to bottle caps as used on milk bottles and the like wherein a separable portion of the cap indicates tampering with the cap so that the purchaser may be assured that the contents of the bottle are as originally packed.
(2) Description of the Prior Art
Snap on bottle caps as heretofore proposed may be seen in U.S. Pat. Nos. 3,411,652; 3,572,413; 3,592,349; 3,872,933 and 4,090,630.
In each of the foregoing disclosures bottle caps are disclosed which theoretically are self-retaining on an appropriately shaped neck of a container such as a bottle. The inherent problem which such devices in the difficulty of removing them if they are formed of a material that is sufficiently rigid to keep the cap in position on the bottle in a liquid tight manner and alternately the leakage of the contents of the bottles if the caps are formed of a flexible material which would facilitate their removal.
Additionally no indication of tampering with or previous removal and replacement of the caps is provided. Attempts have been made to overcome these difficulties and in U.S. Pat. Nos. 3,462,035, reissue 27,648; 3,940,004 and 4,037,746, tear strips or portions facilitating the removal of the cap from the container are provided. The problems with such devices is primarily the difficulty in applying the caps to the containers as the unusual configurations of the tear strips or attachments makes the caps difficult to handle by the automatic equiment which is used in applying the caps to the containers such as milk bottles or the like.
Still further proposals have been made to tear away a portion of an annular flange or skirt on a bottle cap so as to destroy the portions thereof that engages and secures the cap in closed position on the neck of a container. Such devices may be seen in U.S. Pat. Nos. 3,120,900; 3,338,446 and 3,392,862.
The present invention overcomes the several difficulties experienced with the prior art bottle caps by providing a relatively small cap of resilient material in a form that will be self-retaining when snapped into position on a bottle having a neck configuration including an out-turned annular shoulder and which may be relatively easily removed by separating most of an annular reinforcing ring from the cap to form a full ring attached to a portion of the annular flange of the cap which permits the circumference of the cap to be expanded so as to free the same from the shoulder on the bottle and at the same time to provide a tell-tale indication that the cap has been removed and/or replaced.